Right ventricular dilation in primary amyloidosis: an independent predictor of survival

Transthyretin Amyloid Cardiomyopathy: Current Diagnostic Approach and Risk Stratification with Multimodality Imaging

Amyloidosis is an infiltrative disease that may cause cardiomyopathy if the precursor protein that misfolds and forms the amyloid is transthyretic or plasma abnormal light chains. Transthyretin amyloid cardiomyopathy has to be diagnosed timely and accurately since there are specific treatment options to support the patients. Multimodality imaging including electrocardiography, echocardiography with strain imaging and cardiac magnetic resonance applying late gadolinium enhancement imaging, native T1 mapping and extracellular volume, raise a high suspicion of the disease and bone scintigraphy set the diagnosis even without the need of biopsy. However, the morbidity and mortality remain high and the need for risk stratification and assessment of the response to treatment are of paramount importance. Cardiac imaging biomarkers offer a thoughtful insight into the prognosis of these patients at diagnosis and after treatment. The current narrative review aims to enlighten the use of multimodality cardiac imaging in transthyretic amyloid cardiomyopathy throughout the disease pathogenesis and evolution from diagnosis to prognosis and response to treatment in a personalized manner.

Prognostic value of echocardiographic cardiac chamber longitudinal strains in advanced light chain cardiac amyloidosis

OBJECTIVE

Patients with advanced light chain cardiac amyloidosis (AL-CA) have a poor prognosis. We aimed to (1) assess the prognostic significance of all cardiac chamber longitudinal strains and (2) to further determine whether the combination of longitudinal strains with the Mayo staging system could provide additional prognostic value.

METHODS

Patients classified as Mayo 2012 stage III and IV were included in our study. We documented major adverse cardiac events (MACEs), including hospitalization for heart failure and all-cause mortality. Right ventricular free wall strain (RV-FWS), left ventricular global longitudinal strain (LV-GLS), left atrial longitudinal peak strain (LAPS), and right atrial longitudinal peak strain (RAPS) were assessed using echocardiography.

RESULTS

This research enrolled 140 advanced AL-CA patients, with 49.3% at Mayo 2012 stage IV. During follow-up, 84 patients developed MACEs. LV-GLS, RV-FWS, LAPS, and RAPS were independent risk factors for advanced AL-CA patients. Kaplan-Meier curves revealed that cutoff values of all heart-chamber longitudinal strains had significant additional prognostic values for the Mayo 2012 stage. According to multivariate Cox regression, Age, gender, Mayo 2012, LAPS, RAPS, RV-FWS, and LV-GLS were included in the predictive model. The AUCs of the Model were 0.887, 0.907, and 0.883 for 1-, 3-, and 5-year MACEs, respectively. The model was internally validated using 200 bootstrapped resamples, yielding a corrected C-index of 0.810. A nomogram was developed and dynamically accessed via the following link: https://lxhadvancedalliexiantu.shinyapps.io/ALCA/.

CONCLUSION

In patients with advanced AL-CA, it is essential to thoroughly evaluate all cardiac chamber longitudinal strains, particularly focusing on LV-GLS, RV-FWS, LAPS, and RAPS.

Diagnostic and therapeutic challenges in rapidly progressing cardiac amyloidosis: a literature review based on case report

INTRODUCTION

Cardiac amyloidosis is a rarely reported and potentially fatal variant of the systemic disease. Its early diagnosis could potentially lead to significantly improved clinical outcomes.

CASE PRESENTATION

A 56-year-old female presented with dyspnea and palpitations. Her physical exam and non-invasive evaluation with cardiac magnetic resonance imaging (CMRI) revealed restrictive cardiomyopathy, and the bone marrow biopsy results showed systemic amyloidosis.

DISCUSSION

The diagnosis of cardiac amyloidosis is not always straightforward, and delay can cause the progression of the disease and an increased risk of morbidity and mortality. Electrocardiograms, echocardiograms, cardiac magnetic resonance imaging, and histopathologic evaluation are the main methods for diagnosing cardiac amyloidosis. The treatment consists of controlling heart failure symptoms and disease-modifying interventions, including medical and surgical therapeutic methods.

CLINICAL LEARNING POINT (CONCLUSION)

Cardiac involvement is the main cause of death in systemic amyloidosis. Early suspicion, diagnosis, and treatment are crucial in improving patients' survival. CMRI can play an essential role in the diagnosis of cardiac Amyloidosis. A graphical abstract is provided for visual summary.

Monitoring cardiac amyloidosis with multimodality imaging

Cardiac amyloidosis (CA) refers to an infiltrative process involving amyloid fibril deposition in the myocardium causing restrictive cardiomyopathy. While various types can affect the heart, the predominant forms are immunoglobulin light-chain (AL) amyloidosis and transthyretin (ATTR) amyloidosis. This review article explores the expanding field of imaging techniques used to diagnose AL-CA and ATTR-CA, highlighting their usefulness in prognostication and disease surveillance. Echocardiography is often the initial imaging modality to suspect CA and, since the incorporation of nonbiopsy criteria using bone scintigraphy, diagnosing ATTR-CA has become more attainable following exclusion of plasma cell dyscrasia. Cardiac magnetic resonance is progressively emerging as a vital tool for imaging CA, and is used in diagnosis, prognostication, and disease surveillance. The use of cardiac magnetic resonance in AL-CA is discussed, as it has been shown to accurately evaluate organ response to chemotherapy. As novel drug treatments emerge in the realm of ATTR-CA, the use of cardiovascular imaging surveillance to monitor disease progression is discussed, as it is gaining prominence as a critical consideration. The ongoing phase III trials investigating treatments for patients with ATTR-CA, will undoubtedly enhance our understanding of cardiac imaging surveillance.

British Society of Echocardiography guideline for the transthoracic echocardiographic assessment of cardiac amyloidosis

These guidelines form an update of the BSE guideline protocol for the assessment of restrictive cardiomyopathy (Knight et al. in Echo Res Prac, 2013). Since the original recommendations were conceived in 2013, there has been an exponential rise in the diagnosis of cardiac amyloidosis fuelled by increased clinician awareness, improvements in cardiovascular imaging as well as the availability of new and effective disease modifying therapies. The initial diagnosis of cardiac amyloidosis can be challenging and is often not clear-cut on the basis of echocardiography, which for most patients presenting with heart failure symptoms remains the first-line imaging test. The role of a specialist echocardiographer will be to raise the suspicion of cardiac amyloidosis when appropriate, but the formal diagnosis of amyloid sub-type invariably requires further downstream testing. This document seeks to provide a focused review of the literature on echocardiography in cardiac amyloidosis highlighting its important role in the diagnosis, prognosis and screening of at risk individuals, before concluding with a suggested minimum data set, for use as an aide memoire when reporting.

Current Status of Radionuclide Imaging of Transthyretin Cardiac Amyloidosis

Cardiac single photon emission computed tomography using 99mTc-bone avid tracers allows for an accurate noninvasive diagnosis of transthyretin (ATTR) cardiac amyloidosis, a historically underdiagnosed disease. This imaging is recommended in select populations who demonstrate clinical and imaging features of infiltrative cardiomyopathy. It is imperative to concomitantly assess for light chain (AL) cardiac amyloidosis independent of radionuclide scintigraphy for timely management of AL amyloidosis, a deadly disease requiring urgent therapy. Clinical judgement is also key and in some select scenarios an endomyocardial biopsy may be needed even after a noninvasive evaluation.

Prognostic role of three-dimensional speckle-tracking echocardiography-derived left ventricular global longitudinal strain in cardiac amyloidosis: Insights from the MAGYAR-Path Study

INTRODUCTION

Systemic amyloidosis is an uncommon disorder in which amyloid fibrils deposit extracellularly. Three-dimensional speckle-tracking echocardiography (3DSTE) is a novel method able to assess left ventricular (LV) global longitudinal strain (GLS). Our aim was to evaluate the prognostic impact of 3DSTE-derived LV-GLS in patients with cardiac amyloidosis (CA).

MATERIALS AND METHODS

A total of 35 patients suffering from light-chain (AL) CA or transthyretin (TTR) CA were selected, but 7 patients had to be excluded due to insufficient image quality or were lost for follow-up. With AL-CA 23 cases, while for TTR-CA 5 patients were diagnosed. Complete two-dimensional Doppler and 3DSTE were performed in all subjects.

RESULTS

The median follow-up was 201 days (ranging from 36 to 632 days) during which cardiovascular event was detected in 17 CA patients, including 8 cardiac deaths. Six patients were diagnosed with acute heart failure, two patients needed invasive interventions (percutaneous coronary intervention with stent-implantation, implantable cardioverter defibrillator implantation) and in one patient new higher grade atrioventricular block was registered. Using ROC analysis, 3DSTE-derived LV-GLS ≥11.8% (absolute value) was found to be a significant predictor for cardiovascular event-free survival (sensitivity 65%, specificity 64%, area under the curve 0.71, p = .05). Lower LV ejection fraction was confirmed in patients with LV-GLS <11.8% as compared to cases with LV-GLS ≥11.8%. In case of a cardiovascular event, LV-GLS was lower as compared to that of subjects with no events. Multivariable regression analysis confirmed that LV-GLS and LV end-diastolic diameter were independent predictors of cardiovascular survival.

CONCLUSION

3DSTE-derived LV-GLS is an independent predictor for future cardiovascular events in CA patients.

Bad players in AL amyloidosis in the current era of treatment

INTRODUCTION

Systemic AL amyloidosis (ALA) is a clonal plasma cell (PC) disease characterized by deposition of amyloid fibrils in different organs and tissues. Traditionally, the prognosis of ALA is poor and is primarily defined by cardiac involvement. The modern prognostic models are based on cardiac markers and free light chain difference (dFLC). Cardiac biomarkers have low specificity and are dependent on renal function, volume status, and cardiac diseases other than ALA. New therapies significantly improved the prognosis of the disease. The advancements in technologies - cardiac echocardiography (ECHO) and cardiac MRI (CMR), as well as new biological markers, relying on cardiac injury, inflammation, endothelial damage, and clonal and non-clonal PC markers are promising.

AREAS COVERED

An update on the prognostic significance of cardiac ALA, number of involved organs, response to treatment, including minimal residual disease (MRD), ECHO, MRI, and new biological markers will be discussed. The literature search was done in PubMed and Google Scholar, and the most recent and relevant data are included.

EXPERT OPINION

Prospective multicenter trials, evaluating multiple clinical and laboratory parameters, should be done to improve the risk assessment models in ALA in the modern era of therapy.

A Review of Cardiac Amyloidosis: Presentation, Diagnosis, and Treatment

Amyloidosis is a group of disorders that can affect almost any organ due to the misfolding of proteins with their subsequent deposition in various tissues, leading to various disease manifestations based on the location. When the heart is involved, amyloidosis can manifest with a multitude of presentations such as heart failure, arrhythmias, orthostatic hypotension, syncope, and pre-syncope. Diagnosis of cardiac amyloidosis can be difficult due to the non-specific nature of symptoms and the relative rarity of the disease. Amyloidosis can remain undiagnosed for years, leading to its high morbidity and mortality due to this delay in diagnosis. Newer imaging modalities, such as cardiac magnetic resonance imaging, advanced echocardiography, and biomarkers, make a timely cardiac amyloidosis diagnosis more feasible. Many treatment options are available, which have provided new hope for this patient population. This manuscript will review the pathology, diagnosis, and treatment options available for cardiac amyloidosis and provide a comprehensive overview of this complicated disease process.

Independent prognostic value of left ventricular mass index in patients with light-chain amyloidosis

BACKGROUND

Echocardiographic-determined left ventricular mass index (LVMI) provides quantitative information on left-ventricular structure. However, its prognostic value on light-chain (AL) amyloidosis has not been clearly defined.

METHODS

We included 99 patients with newly diagnosed AL amyloidosis between July 2013 and March 2022. Clinical features and echocardiographic parameters were collected.

RESULTS

LVMI ≥113.4 g/m² was predictive for overall survival (OS) and progression-free survival (PFS) with respective hazard ratios (HRs) of 2.87 (95% CI: 1.04-7.79) and 2.91 (95% CI: 1.25-6.68). Patients in the LVMI-high group had higher NT-proBNP, cTnT, and FLC-diff levels. They were more likely to be cardiac involved and have increased mean left ventricular wall thickness, decreased left ventricular ejection fraction, and higher proportion of patients with pericardial effusion. In subgroup analysis, LVMI-high group was associated with a reduced OS [HR: 4.74 (95% CI: 1.26-17.77)] and PFS [HR: 7.16 (95% CI: 2.10-24.40)] in patients with cardiac amyloidosis (CA). Besides, LVMI-high was associated with a reduced OS [HR: 3.58 (95% CI: 1.17-11.02)] and PFS [HR: 4.79 (95% CI: 1.77-12.94), p = 0.00] among patients staged of II or III (Mayo 2004), as well as reduced OS [HR: 22.65 (95% CI: 1.66-299.31)] and PFS [HR: 18.73 (95% CI: 2.36-148.35)] among patients staged of III or IV (Mayo 2012).

CONCLUSIONS

LVMI is a reliable prognostic indicator of survival. A cut-off of LVMI (113.4 g/m²) was prognostic for OS and PFS. Importantly, LVMI was able to identify a subset of patients with poorer prognosis in the context of CA or in the late stages according to the biomarker staging systems.

Three-Dimensional Echocardiography Assessment of Right Ventricular Volumes and Function: Technological Perspective and Clinical Application

Right ventricular (RV) function has important prognostic value in a variety of cardiovascular diseases. Due to complex anatomy and mode of contractility, conventional two-dimensional echocardiography does not provide sufficient and accurate RV function assessment. Currently, three-dimensional echocardiography (3DE) allows for an excellent and reproducible assessment of RV function owing to overcoming these limitations of traditional echocardiography. This review focused on 3DE and discussed the following points: (i) acquisition of RV dataset for 3DE images, (ii) reliability, feasibility, and reproducibility of RV volumes and function measured by 3DE with different modalities, (iii) the clinical application of 3DE for RV function quantification.

Multimodality Imaging in the Evaluation and Prognostication of Cardiac Amyloidosis

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy resulting from deposition of misfolded immunoglobulin light chains (AL-CA) or transthyretin (ATTR-CA) proteins in the myocardium. Survival varies between the different subtypes of amyloidosis and degree of cardiac involvement, but accurate diagnosis is essential to ensure initiation of therapeutic interventions that may slow or potentially prevent morbidity and mortality in these patients. As there are now effective treatment options for CA, identifying underlying disease pathogenesis is crucial and can be guided by multimodality imaging techniques such as echocardiography, magnetic resonance imaging, and nuclear scanning modalities. However, as use of cardiac imaging is becoming more widespread, understanding optimal applications and potential shortcomings is increasingly important. Additionally, certain imaging modalities can provide prognostic information and may affect treatment planning. In patients whom imaging remains non-diagnostic, tissue biopsy, specifically endomyocardial biopsy, continues to play an essential role and can facilitate accurate and timely diagnosis such that appropriate treatment can be started. In this review, we examine the multimodality imaging approach to the diagnosis of CA with particular emphasis on the prognostic utility and limitations of each imaging modality. We also discuss how imaging can guide the decision to pursue tissue biopsy for timely diagnosis of CA.

Right Ventricular Function Improves Early After Percutaneous Mitral Valve Repair in Patients Suffering From Severe Mitral Regurgitation

Background

Percutaneous mitral valve edge-to-edge procedure (PMVR) using the MitraClip^® system (Abbot Vascular, CA) is an established therapy for severe mitral regurgitation (MR) in patients judged inoperable or at high surgical risk. Besides determining exercise capacity, right ventricular (RV) function has prognostic value in heart failure and after cardiac surgery. We therefore investigated the impact of PMVR on RV function in patients with severe MR.

Methods and Results

Sixty-three patients undergoing PMVR at our department were prospectively enrolled. Transthoracic echocardiography was performed before, early (2–12d) after PMVR and after 3 months, including advanced echocardiographic analyses such as 3D imaging and strain analyses. At baseline, all patients presented with advanced heart failure symptoms. Etiology of MR was more often secondary and, if present, left ventricular (LV) dysfunction was predominantly caused by ischemic cardiomyopathy. PMVR substantially reduced MR to a grade ≤ 2 in most patients. Echocardiographic assessment revealed a largely unchanged LV systolic function early after PMVR, while in contrast RV function substantially improved after PMVR [3D RV EF (%): pre 33.7% [27.4; 39.6], post 40.0% [34.5; 46.0] (p < 0.01 vs. pre), 3 months 42.8% [38.3; 48.1] (p < 0.01 vs. pre); 2D RV GLS (%): pre −12.9% [−14.5; −10.5], post −16.0% [−17.9; −12.6] (p < 0.01 vs. pre), 3 months −17.2% [−21.7; −14.9] (p < 0.01 vs. pre)]. Factors that attenuated RV improvement were larger ventricular volumes, lower LV function, secondary MR, and a higher STS score (all p < 0.05).

Conclusion

By using advanced echocardiographic parameters, we discovered an early improvement of RV function after PMVR that is preserved for months, independent from changes in LV function. Improvement of RV function was less pronounced in patients presenting with an advanced stage of heart failure and a higher burden of comorbidities reflected by the STS score.

Echocardiographic assessment of cardiac amyloidosis

Cardiac amyloidosis, a form of infiltrative cardiomyopathy, is associated with poor prognosis in untreated patients. Early diagnosis is important for timely initiation of effective therapies. Despite advances in diagnostic modalities, it remains a challenging diagnosis, requiring high index of clinical suspicion. Echocardiography represents the first-line cardiac imaging modality for evaluation of heart failure and suspected cardiac amyloidosis. In this review, we discuss echocardiographic findings in cardiac amyloidosis.

Diagnostic and prognostic value of cardiac imaging in amyloidosis

Amyloidosis is an infiltrative disease caused by extracellular protein deposition that has accumulated a lot of scientific production in recent years. Different types of amyloidosis can affect the heart. Transthyretin amyloidosis and light chain amyloidosis are the two most common types of cardiac amyloidosis. These entities have a poor prognosis, so accurate diagnostic techniques are imperative for determining an early therapeutic approach. Recent advances in cardiac imaging and diagnostic strategies show that these tools are safe and can avoid the use of invasive diagnostic techniques to histological confirmation, such as endomyocardial biopsy. We performed a review on the diagnostic and prognostic implications of different cardiac imaging techniques in cardiac amyloidosis. We mainly focus on reviewing echocardiography, cardiac magnetic resonance, computed tomography and nuclear imaging techniques and the different safety measurements that can be done with each of them.

Multi-modality imaging in transthyretin amyloid cardiomyopathy

Transthyretin amyloid (TTR) cardiomyopathy is a disease of insidious onset, which is often accompanied by debilitating neurological and/or cardiac complications. The true prevalence is not fully known due to its elusive presentation, being often under-recognized and usually diagnosed only late in its natural history and in older patients. Because of this, effective treatment options are usually precluded by multiple comorbidities and frailty associated with such patients. Therefore, high clinical suspicion with earlier and better detection of this disease is needed. In this review, the novel applications of multimodality imaging in the diagnostic pathway of TTR cardiomyopathy are explored. These include the complimentary roles of transthoracic echocardiography, cardiac magnetic resonance, nuclear scintigraphy and positron emission tomography in quantifying cardiac dysfunction, diagnosis and risk stratification. Recent advances in novel therapeutic options for TTR have further enhanced the importance of a timely and accurate diagnosis of this disease.

How to Image Cardiac Amyloidosis: A Practical Approach

Cardiac amyloidosis (CA) is one of the most rapidly progressive forms of heart disease, with a median survival from diagnosis, if untreated, ranging from <6 months for light chain amyloidosis to 3 to 5 years for transthyretin amyloidosis. Early diagnosis and accurate typing of CA are necessary for optimal management of these patients. Emerging novel disease modifying therapies increase the urgency to diagnose CA at an early stage and identify patients who may benefit from these life-saving therapies. The goal of this review is to provide a practical approach to echocardiography, cardiac magnetic resonance, and radionuclide imaging in patients with known or suspected CA.

Role of echocardiography in assessing cardiac amyloidoses: a systematic review

Cardiac amyloidosis is a manifestation of one of several systemic amyloidoses, and is characterized by increased left-ventricular (LV) wall thickness and normal or decreased LV cavity size. Congestive heart failure in cardiac amyloidosis is characterized by a predominant diastolic LV dysfunction, and systolic dysfunction occurs only in late-stage disease. Echocardiography is a noninvasive, reproducible method for assessing cardiac morphology and function in cardiac amyloidosis, and some echocardiographic indices are prognostic for amyloidoses. This review describes the advances in echocardiography and its role in the diagnosis and management of cardiac amyloidoses. Our review suggests that LV longitudinal function and the cyclic variation of myocardial integrated backscatter may be the best predictors of adverse outcomes. In the future, new echocardiographic techniques, such as fully automated echocardiogram interpretation, should provide further useful information for assessing cardiac function and prognosis in cardiac amyloidosis patients.

Right Atrial Deformation Analysis in Cardiac Amyloidosis - Results from the Three-Dimensional Speckle-Tracking Echocardiographic MAGYAR-Path Study

BACKGROUND

Light-chain (AL) cardiac amyloidosis (CA) is characterized by fibril deposits, which are composed of monoclonal immunoglobulin light chains. The right ventricle is mostly involved in AL-CA and impairment of its function is a predictor of worse prognosis.

OBJECTIVES

To characterize the volumetric and functional properties of the right atrium (RA) in AL-CA by three-dimensional speckle-tracking echocardiography (3DSTE).

METHODS

A total of 16 patients (mean age: 64.5 ± 10.1 years, 11 males) with AL-CA were examined. Their results were compared to that of 15 age- and gender-matched healthy controls (mean age: 58.9 ± 6.9 years, 8 males). All cases have undergone complete two-dimensional Doppler and 3DSTE. A two-tailed p value of less than 0.05 was considered statistically significant.

RESULTS

Significant differences could be demonstrated in RA volumes respecting cardiac cycle. Total (19.2 ± 9.3% vs. 27.9 ± 10.7%, p = 0.02) and active atrial emptying fractions (12.1 ± 8.1 vs. 18.6 ± 9.8%, p = 0.05) were significantly decreased in AL-CA patients. Peak global (16.7 ± 10.3% vs. 31.2 ± 19.4%, p = 0.01) and mean segmental (24.3 ± 11.1% vs. 38.6 ± 17.6%, p =0.01) RA area strains, together with some circumferential, longitudinal and segmental area strain parameters, proved to be reduced in patients with AL-CA. Global longitudinal (4.0 ± 5.2% vs. 8.2 ± 5.5%, p = 0.02) and area (7.8 ± 8.1% vs. 15.9 ± 10.3%, p = 0.03) strains at atrial contraction and some circumferential and area strain parameters at atrial contraction were reduced in AL-CA patients.

CONCLUSION

Significantly increased RA volumes and deteriorated RA functions could be demonstrated in AL-CA.

Which echocardiographic parameters improve the risk prediction for peri-operative outcomes in patients undergoing coronary bypass surgery: a prospective study

OBJECTIVE

To assess the performance of transthoracic echocardiographic parameters to predict operative mortality and morbidity in patients undergoing coronary artery bypass grafting, and to assess its incremental prognostic value as compared to the Society of Thoracic Surgeons (STS) score.

MATERIALS AND METHODS

We prospectively collected the clinical and biological data required to calculate the STS score in patients hospitalised for coronary artery bypass grafting. Preoperative transthoracic echocardiography was performed for each patient. The primary endpoint was 30-day mortality or major morbidity (i.e. stroke, renal failure, prolonged ventilation, deep sternal wound infection, reoperation) as defined by the STS. The secondary endpoint was prolonged hospitalisation for over 14 days.

RESULTS

A total of 172 patients was included (mean age 66.1±10.2 years, 12.2% were women). The primary endpoint occurred in 33 patients (19.2%), and 28 patients (16.3%) had a prolonged hospital stay. Independent predictive factors for the primary endpoint were an increased left atrial volume (>31 mL/m²; odds ratio (OR) 3.55, 95% confidence interval (CI) 1.38-9.12; P=0.004) and a decreased tricuspid annular plane systolic excursion (<20 mm; OR 3.45, 95% CI 1.47-8.21; P=0.008). The predictive value of the multivariate model increased when the two echocardiographic parameters were added to the STS score (area under the curve 0.598 vs. 0.695, P=0.001; integrated discrimination improvement 7.44%).

CONCLUSION

In patients undergoing coronary artery bypass grafting, preoperative assessment of left atrial size and tricuspid annular plane systolic excursion should be performed systematically, as it provides additional prognostic information to the STS score.

Recent Advances in Cardiovascular Imaging Relevant to the Management of Patients with Suspected Cardiac Amyloidosis

Cardiac amyloidosis is a form of infiltrative cardiomyopathy typically presenting with progressive heart failure. The clinical presentation and morphological findings often overlap with other cardiovascular diseases, and frequently results in misdiagnosis and consequent under-reporting. Cardiovascular imaging is playing an increasingly important diagnostic and prognostic role in this referral population, and is reducing the reliance on endomyocardial biopsy as a confirmatory testing. Advancements across multiple cardiac imaging modalities, including echocardiography, magnetic resonance imaging, nuclear imaging, and computed tomography, are improving diagnostic accuracy and offering novel approaches to sub-type differentiation and prognostication. This review explores recent advancements in cardiac imaging for the diagnosis, typing, and staging of cardiac amyloidosis, with a focus on new and evolving techniques. Emphasis is also placed on the promise of non-invasive cardiac imaging to provide value across the spectrum of this clinical disease, from early disease identification (prior to the development of increased wall thickness) through to markers of advanced disease associated with early mortality.

Cardiac amyloidosis: pathogenesis, clinical context, diagnosis and management options

Amyloidosis covers a group of disorders that can manifest in virtually any organ system in the body and is thought to be secondary to misfolding of extracellular proteins with subsequent deposition in tissues. The precursor protein that is produced in excess defines the specific amyloid type. This requires histopathological confirmation using Congo-red dye with its characteristic demonstration of green birefringence under cross-polarized light. There are three main types of amyloidosis associated with cardiac involvement: light-chain (AL), familial or senile (ATTR), and secondary (AA) amyloidosis. The frequency of cardiac involvement and prognosis varies among each type. Amyloid cardiomyopathy commonly manifests as heart failure and the presenting features are usually dyspnoea, oedema, angina, pre-syncope and syncope. The diagnosis of cardiac amyloidosis is very hard and can easily be misdiagnosed. Although the imaging studies (such as echocardiography and cardiovascular magnetic resonance) may guide the diagnosis, tissue biopsy is needed for confirmation. Management of cardiac amyloidosis initially is to treat the underlying heart failure. Pacemaker implantation is usually required in patients with any conduction abnormalities. Transplantation is the next step with worsening heart failure. However, the aim of any treatment in amyloidosis, irrespective of type, is to prevent further deposition of amyloid while managing concurrent symptoms. In this manuscript, we will discuss the pathogenesis of cardiac amyloidosis, diagnostic methods and management options.

Value of tissue Doppler-derived Tei index and two-dimensional speckle tracking imaging derived longitudinal strain on predicting outcome of patients with light-chain cardiac amyloidosis

Prognosis of patients with light-chain cardiac amyloidosis (AL-CA) is poor. Speckle tracking imaging (STI) derived longitudinal deformation parameters and Doppler-derived left ventricular (LV) Tei index are valuable predictors of outcome in patients with AL-CA. We estimated the prognostic utility of Tei index and deformation parameters in 58 comprehensively phenotyped patients with AL-CA after a median follow-up of 365 days (quartiles 121, 365 days). The primary end point was all-cause mortality. 19 (33%) patients died during follow-up. Tei index (0.89 ± 0.29 vs. 0.61 ± 0.16, p < 0.001) and E to global early diastolic strain rate ratio (E/GLSR_dias) were higher while global longitudinal systolic strain (GLS_sys) was lower in non-survivors than in survivors (all p < 0.05). Tei index, NYHA functional class, GLS_sys and E/GLSR_dias were independent predictors of all-cause mortality risk, and Tei index ≥0.9 (HR 7.01, 95% CI 2.43–20.21, p < 0.001) was the best predictor of poor outcome. Combining Tei index and GLS_sys yielded the best results on predicting death within 1 year (100% with Tei index ≥0.9 and GLS_sys ≤13%) or survival (95% with Tei index ≤0.9 and GLS_sys ≥13%). We conclude that 1-year mortality risk in AL-CA patients can be reliably predicted using Tei index or deformation parameters, with combined analysis offering best performance.

Quantitative assessment of systolic and diastolic function in patients with LGE negative systemic amyloidosis using CMR

OBJECTIVES

In clinical routine myocardial affection in amyloidosis is assessed by qualitative late gadolinium enhancement (LGE). Recent studies suggest that early cardiac involvement in amyloidosis may be overlooked by qualitative LGE assessment. The aim of this study was to assess possible early cardiac involvement in LGE negative AL patients by means of systolic and diastolic strain assessment and quantitative enhancement.

METHODS

51 individuals (17 Patients with LGE positive light-chain amyloidosis (AL) (Group A), 17 Patients with LGE negative systemic AL (Group B), and 17 healthy controls (Group C)) were investigated. SSFP-Cine sequences were acquired in short axis slices as well as horizontal long axis views. Standard CMR parameters as well as Feature Tracking (FT) derived systolic and diastolic circumferential and longitudinal strain parameters were calculated. Additionally, contrast enhanced MRI images were analyzed to quantitatively determine the extent of enhancement.

RESULTS

AL patients with and without LGE both had significantly lower early diastolic strain rate (EDSR) values and peak systolic longitudinal strain (PSLS) values than healthy controls (EDSR: Group A 63.1±17.6; Group B: 74.46±11.8; Group C: 86.82±12.7; F(2.48)=10.7 p<0.001); (PSLS: Group A: -13.44±1.9%; Group B: -20.31±1.2%; Group C: -23.11±1.4%; F(2.48)=167.6; p<0.001). Analysis of quantitative LGE enhancement revealed increased enhancement in qualitative LGE negative AL patients compared to healthy controls (Group A: 19.6±8.9%; Group B: 8.2±3.9%; Group C: 2.4±1.3% F(2.48)=52.2; p<0.001).

CONCLUSION

CMR strain analysis detects early systolic and diastolic strain impairment in AL patients lacking qualitative LGE enhancement.

Clinical and prognostic utility of cardiovascular magnetic resonance imaging in myeloma patients with suspected cardiac amyloidosis

OBJECTIVES

AL amyloidosis affects up to 30% of patients with multiple myeloma (MM), and cardiac involvement is associated with worse outcomes. Traditional screening modalities including EKG, echocardiography and biomarkers have limited value. The aim of this study was to evaluate the clinical and prognostic value of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) imaging in patients with plasma cell dyscrasias and suspected cardiac amyloidosis (CA).

METHODS

A total of 251 consecutive patients with plasma cell dyscrasias who underwent CMR were enrolled in this study. Primary endpoint was all cause mortality. Clinical, ECG, echocardiographic, biomarker and CMR predictors of mortality were analyzed.

RESULTS

Mean age of population was 63 ± 10 years, 36% females and 19% African Americans. During a median follow-up duration of 28 months (IQR 5-56), there were 97 deaths (39%). Patients who died were more likely to have diabetes (28% vs. 14%; P = 0.03), CAD (28% vs. 16%; P = 0.04) and CKD (33% vs. 21%; P = 0.04). With endomyocardial biopsy as the gold standard (42 (17%) patients), amyloid pattern on CMR (LGE+) had sensitivity and negative predictive values of 100%; specificity and positive predictive values of 80 and 81% with an AUC 0.9 for CA. History of CAD (HR 1.64, 95% CI 1.01-2.6; P = 0.04), brain natriuretic peptide (HR 1.0003 95% CI 1.0001-1.0006; P = 0.004) and LGE + (HR 1.72, 95% CI 1.05-2.8; P = 0.02) were independent predictors of mortality. LGE+ possessed incremental prognostic value over clinical, laboratory and echocardiographic variables for mortality prediction.

CONCLUSIONS

CMR is a clinically useful tool for diagnosis and prognostication in myeloma patients with suspected CA.

Diagnosis, Prognosis, and Therapy of Transthyretin Amyloidosis

Transthyretin amyloidosis is a fatal disorder that is characterized primarily by progressive neuropathy and cardiomyopathy. It occurs in both a mutant form (with autosomal dominant inheritance) and a wild-type form (with predominant cardiac involvement). This article guides clinicians as to when the disease should be suspected, describes the appropriate diagnostic evaluation for those with known or suspected amyloidosis, and reviews the interventions currently available for affected patients.

Three-dimensional Speckle Tracking Echocardiography in Light Chain Cardiac Amyloidosis: Examination of Left and Right Ventricular Myocardial Mechanics Parameters

INTRODUCTION AND OBJECTIVES

The study of myocardial mechanics has a potential role in the detection of cardiac involvement in patients with amyloidosis. This study aimed to characterize 3-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics in light chain amyloidosis and examine their relationship with brain natriuretic peptide.

METHODS

In patients with light chain amyloidosis, left ventricular longitudinal and circumferential strain (n=40), and right ventricular longitudinal strain and radial displacement (n=26) were obtained by 3-dimensional-speckle tracking echocardiography. Brain natriuretic peptide levels were determined.

RESULTS

All myocardial mechanics measurements showed differences when compared by brain natriuretic peptide level tertiles. Left and right ventricular longitudinal strain were highly correlated (r=0.95, P<.001). Left ventricular longitudinal and circumferential strain were reduced in patients with cardiac involvement (-9±4 vs -16±2; P<.001, and -24±6 vs -29±4; P=.01, respectively), with the most prominent impairment at the basal segments. Right ventricular longitudinal strain and radial displacement were diminished in patients with cardiac involvement (-9±3 vs -17±3; P<.001, and 2.7±0.8 vs 3.8±0.3; P=.002). On multivariate analysis, left ventricular longitudinal strain was associated with the presence of cardiac involvement (odds ratio = 1.6; 95% confidence interval, 1.04 to 2.37; P=.03) independent of the presence of brain natriuretic peptide and troponin I criteria for cardiac amyloidosis.

CONCLUSIONS

Three-dimensional-speckle tracking echocardiography-derived left and right ventricular myocardial mechanics are increasingly altered as brain natriuretic peptide increases in light chain amyloidosis. There appears to be a strong association between left ventricular longitudinal strain and cardiac involvement, beyond biomarkers such as brain natriuretic peptide and troponin I.

Echocardiographic assessment of the cardiac amyloidoses

Cardiac amyloidosis is a cardiomyopathy characterized by increased left ventricular (LV) wall thickness and normal or decreased LV cavity size. Congestive heart failure in cardiac amyloidosis is generally considered a predominantly diastolic phenomenon, with systolic dysfunction only occurring in late-stage disease. Echocardiography is a noninvasive, reproducible method of assessing cardiac features and function in cardiac amyloidosis, and some echocardiographic indices are prognostic for the amyloidoses, with M-mode and 2-dimensional echocardiography able to detect increased LV wall thickness. Moreover, Doppler flow measurements can incrementally assess diastolic LV dysfunction, which is characteristic of cardiac amyloidosis, and provide important prognostic information. Additionally, tissue Doppler imaging can detect subtle changes in both systolic and diastolic LV function, which cannot be detected by Doppler flow measurements, and LV longitudinal strain assessed by color tissue Doppler and speckle tracking echocardiography can provide more accurate LV functional and prognostic information than tissue Doppler imaging. This review describes the advances in echocardiography and its crucial role in the diagnosis and management of cardiac amyloidosis.

The mosaic of the cardiac amyloidosis diagnosis: role of imaging in subtypes and stages of the disease

Cardiac amyloidosis is a rare, infiltrative cardiomyopathy that presents with thickened ventricular walls and progressive heart failure. The morphological findings and clinical features are shared with many other diseases (i.e. hypertrophic cardiomyopathy, 'athlete's heart,' Fabry disease, and hypertensive cardiomyopathy), and misdiagnosis occurs frequently. Cardiologists have many instruments that can help reach a correct diagnosis in a relatively short time. As tiles of a mosaic are placed to create an image, thoughtful and smart use of the different diagnostic tools available allows the opportunity to identify amyloid infiltration of the myocardium. When the myocardium is involved, prognosis is poor, so identification of its involvement is crucial for disease management. The diagnostic process begins with an accurate evaluation of clinical elements and includes cardiovascular imaging (echocardiography, magnetic resonance, and nuclear medicine), electrocardiography, serological assays, and myocardial biopsy; only the appropriate integration of these instruments can reveal the diagnosis to an expert physician. The latest improvements in non-invasive diagnostic techniques with increased diagnostic power have reduced the need for biopsy.

Current state of cardiac amyloidosis

PURPOSE OF REVIEW

Cardiac amyloidosis, an infiltrative restrictive cardiomyopathy once thought to be universally fatal, is now increasingly recognized as less rare than previously thought. This update is intended to provide a review of newer aspects of the presentation, diagnosis and treatment of cardiac amyloidosis.

RECENT FINDINGS

Amyloid involvement of the heart is increasingly seen, especially in the elderly population. Recent data suggest life expectancy has increased from 6 to 16-20 months in the most common subtype, AL amyloid. The clinical presentation is typically one of heart failure in the setting of normal or low normal ejection fraction, inappropriate ventricular hypertrophy and atrial enlargement with or without atrial fibrillation. Diagnosis is now most often made by cardiac MRI, with 2D echocardiography serving more of a screening role in patients with heart failure or a similar family history. The gold standard diagnostic test is right-ventricular biopsy, which demonstrates positivity for Congo Red staining. Due to a propensity for disease progression, typically low systemic blood pressure, frequent extra-cardiac involvement and autonomic dysfunction, cardiac amyloidosis is difficult to treat due to poor tolerance of most cardiovascular medication and poor outcome for transplantation. Newer therapies such as bortezomib, usually given to patients with multiple myeloma and serum light chains, are promising in controlling amyloidosis.

CONCLUSION

Recent advances in diagnosis and treatment of amyloid are associated with improved prognosis. Newer therapies offer future benefits.

Evaluation of patients with cardiac amyloidosis using echocardiography, ECG and right heart catheterization

AIMS

To characterize patients with cardiac amyloidosis using echocardiography, electrocardiogram (ECG) and right heart catheterization (RHC).

METHODS AND RESULTS

Fourteen patients with biopsy verified light chain or transthyretin cardiac amyloidosis were included. All patients had heart failure with markedly elevated NT-proBNP. Echocardiography demonstrated biventricular hypertrophy, left atrial enlargement and normal to slightly reduced left ventricular ejection fraction. Tissue Doppler septal é was low and median E/é was high. Within 6 months RHC was performed in eight of the patients. The restrictive filling pattern demonstrated by echocardiography corresponded well to median pulmonary wedge pressure (21 mmHg). Systolic pulmonary artery pressure (SPAP) was increased, whereas cardiac output and stroke volume were seen to be decreased with both methods. ECG demonstrated: low voltage (36%), abnormal R-progression (65%), ST-T abnormalities (71%) and high incidence of fibrillation (36%). In addition, a case report following the treatment of melphalan and dexamethasone is presented with improvement of hypertrophy, SPAP, left ventricular mass and é.

CONCLUSION

These findings should lead to a suspicion of cardiac amyloidosis and suggest further investigation.

Three-dimensional transesophageal echocardiography for perioperative right ventricular assessment

BACKGROUND

In high-risk cardiac procedures, dynamic analysis of right ventricular (RV) performance is desirable, but the geometric complexity of the RV limits the applicability of current two-dimensional echocardiographic imaging techniques. This study aimed to evaluate the utility of three-dimensional transesophageal echocardiography (TEE) for the perioperative assessment of RV function and dimensions.

METHODS

Patients undergoing cardiac surgical procedures with complete TEE examinations were identified and reviewed according to current guidelines to exclude patients with significant coexisting valvular regurgitation. Full-volume, three-dimensional datasets were analyzed by two independent investigators using stand-alone software, and left ventricular and RV dimensions were recorded.

RESULTS

Datasets from 50 patients undergoing cardiac surgical procedures were evaluated for this study. The mean RV volume was 111.7 mL (range, 37.5 to 349.7 mL) at end diastole and 67.6 mL (range, 25.5 to 274.4 mL) at end systole. Intraobserver reliability was 0.93 and 0.90 for end diastolic and 0.77 and 0.87 for end systolic volumes. The interobserver reliability for RV volumes was 0.83 at end diastole and 0.86 at end systole. The mean stroke volume was 43.6 mL (range, 12 to 111.2 mL) for the RV and 49.1 mL (range, 19.9 to 102.8 mL) for the left ventricle; the correlation coefficient between the two was 0.85.

CONCLUSIONS

Three-dimensional TEE volumetric measurements were reproducible across a wide range of RV dimensions. As postulated by the continuity principle, stroke volume measurements between both ventricles correlated well, supporting the validity of this approach. Therefore, our work provides preliminary evidence that three-dimensional TEE offers reproducible information about RV function and size in the dynamic and complex perioperative setting of cardiac surgical procedures.

What do I need to know about immunoglobulin light chain (AL) amyloidosis?

Immunoglobulin light chain (AL) amyloidosis is the most common acquired systemic amyloidoses. Its presentation is often insidious and progressive, which may delay diagnosis. The interval between first symptoms and actual diagnosis along the intrinsic heterogeneity of tissue tropism create a wide spectrum of presentations, both in terms of scope and depth of symptoms and signs and functional status of patients. In this review, the authors review the pathogenesis, diagnosis and differential diagnosis of AL amyloidosis along with the prognosis and state-of-the-art management for patients with this affliction.

Comparison of right ventricular longitudinal strain imaging, tricuspid annular plane systolic excursion, and cardiac biomarkers for early diagnosis of cardiac involvement and risk stratification in primary systematic (AL) amyloidosis: a 5-year cohort study

AIMS

To determine the role of assessing right ventricular (RV) function, using standard echocardiography and Doppler myocardial imaging (DMI), in the early diagnosis of cardiac amyloidosis and in the prediction of mortality.

METHODS AND RESULTS

Patients with primary systemic (AL) amyloidosis seen at our institution from 1 February 2004 through 31 October 2005 (N=249) were categorized by left ventricular thickness and E' velocity and compared with 38 age- and sex-matched controls. Standard echocardiographic and DMI examination were used to measure echocardiographic parameters of RV function: systolic tissue velocity, strain rate, and strain were determined for basal and middle RV free wall segments. Patients were followed up for the endpoint of mortality. RV tricuspid annular plane systolic excursion (TAPSE) and all DMI measurements were lower in patients with AL amyloidosis and normal echocardiography results (AL-normal-echo group) than controls. A bivariate model including strain of the basal segment of the RV free wall and TAPSE was the best for distinguishing AL-normal-echo patients from controls. Male sex [hazard ratio (HR), 2.2; P=0.005], brain natriuretic peptide levels (HR 1.4; P=0.003), troponin T levels (HR 1.6; P=0.01), pleural effusion (HR 3.6; P<0.001), E/A ratio (HR 1.3; P=0.006), RV systolic pressure (HR 1.02; P=0.01), and RV strain rate of the middle segment (HR 1.3; P=0.02) were independent predictors of death.

CONCLUSION

DMI measures of the RV can identify early impairment of cardiac function or stratify risk of death in patients with AL amyloidosis. Further studies with longer follow-up are warranted to confirm these results.

Echocardiographic evaluation of systolic and diastolic function in patients with cardiac amyloidosis

The typical appearance of cardiac amyloidosis using standard echocardiographic techniques is usually a late finding only in patients with relatively advanced stages of the disease. Early noninvasive identification of cardiac amyloidosis is of growing clinical importance. Newer echocardiographic techniques, including tissue Doppler imaging and deformation imaging (strain rate imaging and 2-dimensional speckle tracking), are powerful tools for quantifying regional myocardial motion and deformation. Using these advanced techniques, early functional impairment in cardiac amyloidosis may be detectable when the results of standard echocardiography are still normal or inconclusive. This review provides a comprehensive overview of the different echocardiographic approaches for the assessment of systolic and diastolic function in patients with cardiac amyloidosis. Special attention is paid to regional myocardial function assessed by tissue Doppler imaging, strain rate imaging, and 2-dimensional speckle-tracking imaging.

Pressure-volume relationships in patients with transthyretin (ATTR) cardiac amyloidosis secondary to V122I mutations and wild-type transthyretin: Transthyretin Cardiac Amyloid Study (TRACS)

BACKGROUND

ATTR cardiac amyloidosis can result from a mutated variant of transthyretin (eg, V122I) or wild-type variant (ATTRwt). We evaluated pressure-volume (PV) indices at baseline and over time to further characterize abnormal pump function in these subjects.

METHODS AND RESULTS

Twenty-nine subjects (18 with ATTRwt and 11 with ATTRm (V122I) had 2-dimensional echocardiograms with complete Doppler measures at baseline and every 6 months for up to 2 years. PV indices were derived from echocardiographic measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVA(iso)), were calculated. Clinical, demographic, and PV indices were compared between V122I and ATTRwt subjects and between survivors and nonsurvivors at baseline and over time. Cox proportional hazards model identified correlates for mortality. Stroke volume decline was associated with alterations in ventricular-vascular coupling and a decrease in ventricular capacitance with significant decrement in ejection fraction (56±12% to 48±14%, P=0.0001) over 18 months. PVA(iso) was lower in V122I subjects compared with wild-type at baseline and declined over time. Twelve (41%) subjects died or underwent a cardiac transplant after a mean follow-up of 478 days (range, 31 to 807). Multivariable survival analysis demonstrated that initial ejection fraction (a measure of ventricular-vascular coupling) <50% was associated with increased mortality (hazard ratio, 6.6; 95% confidence interval, 1.1 to 40.3).

CONCLUSIONS

In ATTR cardiac amyloidosis secondary to a V122I mutation and wild-type transthyretin, PV analysis reveals alterations that are associated with reductions in the ability of the ventricle to perform work and, ultimately, with reduced survival in these subjects.